Telecommunications devices utilizing optical fibers typically have hermetically-sealed metal housings to protect the internal components of the device from temperature variations, moisture, and other environmental contaminants. These sealed housings have at least one aperture that permits an optical fiber to enter and exit the device. It is desirable to maintain a hermetic seal between the optical fiber and the aperture to prevent those contaminants excluded by the housing from entering through the aperture.
These device housings are typically made from a ferrous material or a non-ferrous metallic material such as titanium alloy, magnesium alloy, or aluminum alloy. The choice of a non-ferrous metallic housing may be advantageous due to a number of design factors, such as weight, heat transfer properties, CTE properties, or configurations. However, the use of a non-ferrous metallic housing prohibits the use of soldering to establish a hermetic seal between the optical fiber and the aperture, since there is a poor CTE match between a glass fiber and a non-ferrous metallic material such as titanium alloy, magnesium alloy, or aluminum alloy. Moreover, non-ferrous alloys are not easily plated and, therefore, are not easily receptive to a solder joint.
A need therefore exists for methods and apparatus that permit the establishment of a hermetic seal between an optical fiber and a non-ferrous metallic housing.